A Multicenter Prospective Interventional Trial of Therapeutic Angiogenesis Using Bone Marrow-Derived Mononuclear Cell Implantation for Patients With Critical Limb-Threatening Ischemia Caused by Thromboangiitis Obliterans

Background: Thromboangiitis obliterans (TAO) can lead to the development of critical limb-threatening ischemia (CLTI). Despite conventional treatments, such as smoking cessation or revascularization, young patients (<50 years) still require limb amputation. Therapeutic angiogenesis using bone marrow-derived mononuclear cell (BM-MNC) implantation has been tested and shown to have reasonable efficacy in CLTI. In this multicenter prospective clinical trial, we evaluated the safety and efficacy of BM-MNC implantation in CLTI patients with TAO. Methods and Results: We enrolled 22 CLTI patients with skin perfusion pressure (SPP) <30 mmHg. The primary endpoint of this trial is the recovery of SPP in the treated limb after a 180-day follow-up period. Secondary endpoints include the pain scale score and transcutaneous oxygen pressure (TcPO2). One patient dropped out during follow-up, leaving 21 patients (mean age 48 years, 90.5% male, Fontaine Class IV) for analysis. BM-MNC implantation caused no serious adverse events and increased SPP by 1.5-fold compared with baseline. Surprisingly, this effect was sustained over the longer term at 180 days. Secondary endpoints also supported the efficacy of this novel therapy in relieving pain and increasing TcPO2. Major amputation-free and overall survival probabilities at 3 years among all enrolled patients were high (95.5% and 89.5%, respectively). Conclusions: BM-MNC implantation showed safety and significant efficacy in CLTI patients with TAO.